On July 20, 2006, the United States Senate voted to renew the Voting Rights Act for 25 more years. The vote was unanimous, 98 to 0. That followed an overwhelmingly bipartisan vote in the House of Representatives, which passed it by a vote of 390 to 33. President George Bush signed the renewal with apparent enthusiasm a few days later.

This bipartisan support for the Voting Rights Act — first enacted into law 50 years ago this month by Lyndon B. Johnson — was not unusual; indeed, it was the rule throughout most of the legislation’s history on Capitol Hill. And if you want to understand how dramatically Congress’s partisan landscape has changed in the Obama era, it’s a particularly useful example.

As it happens, two bills introduced in the past two years would restore at least some of the act’s former strength, after the 2013 Supreme Court decision in Shelby v. Holder, which significantly weakened it. And both are languishing, with no significant Republican support and no Republican leader willing to bring them to the floor for a vote. What was, less than a decade ago, an uncontroversial legislative no-brainer is now lost in the crevasse of our partisan divide.

The newly inhospitable climate the Voting Rights Act faces on Capitol Hill is largely the result of the 50-year effort to weaken the law that I wrote about in the magazine’s Aug. 2 cover story, conducted by a small group of ideologues and activists intent on weakening its strongest provisions. And the change threatens to render President Obama’s recent calls for the “restoration” of the act — which he reiterated in a letter to the magazine today — moot for as long as Congress maintains its current partisan makeup.

“There is not any way these bills can move without Republican support,” Representative John Lewis, Democrat of Georgia, a supporter of the legislation and a major figure during the fight for voting rights in the 1960s, told me.

Most of the activity around the Voting Rights Act since its inception has involved its Section 5, which came to require some 15 states with histories of institutional discrimination at the ballot box to submit any changes in their statewide voting laws to federal authorities for approval. From the outset, the provision raised hackles throughout the South, and it continued to be a target of conservative critics of the law, who by the early 1980s were arguing that the law had done such a good job enfranchising blacks that Section 5 was no longer needed.

Still, when Congress last renewed the Act in 2006, it declared, “Despite the progress made by minorities under the Voting Rights Act of 1965, the evidence before Congress reveals that 40 years has not been a sufficient amount of time to eliminate the vestiges of discrimination following nearly 100 years of disregard for the dictates of the 15th Amendment and to ensure that the right of all citizens to vote is protected as guaranteed by the Constitution.”

Even after the Supreme Court gutted Section 5, there were still some Republican voices among the decision’s critics, who promised to help restore the act to its former strength through new legislation. “I’m hopeful Congress will put politics aside,” Representative Eric Cantor of Virginia, then the Republican minority leader in the House, said, “and find a responsible path forward that ensures the sacred obligation of voting in this country remains protected.”

Representative Jim Sensenbrenner, a Wisconsin Republican who helped shepherd the 2006 reauthorization through the House, vowed to introduce new language that would ensure comparable protections and pass court scrutiny. But other Republican leaders — including the House Speaker, John Boehner, and the Senate majority leader, Mitch McConnell — did not join them. And soon afterward, Republicans in states like North Carolina and Texas went on to pass some of the most restrictive voting laws in decades, with many provisions falling disproportionately on minorities.

The first real attempt at a fix in Congress came last year, when Sensenbrenner teamed up with Representative John Conyers, Democrat of Michigan, and Senator Patrick Leahy, Democrat of Vermont. Under their proposed bill, states that had five voting violations in a 15-year period would fall under federal scrutiny. That formula would have immediately affected Georgia, Louisiana, Texas and Mississippi, and made it far easier to add new states under another provision for states whose laws have the effect of diminishing minority-voting strength.

The proposed law only initially captured those four states, and also went easy on voter ID provisions, in a bid for critical Republican support — specifically that of Cantor, who said he was open to supporting it. The law was criticized by civil rights groups for being too soft, but Doug Heye, a former senior aide to Cantor, told me, “He knew there were problems, he wanted to fix them, and was willing to work to improve that bill.”

Cantor’s backing would have potentially helped bring along enough Republicans to pass the bill. But then Cantor lost his primary, effectively eliminating Sensenbrenner’s most important Republican ally.

Earlier this summer Leahy and Lewis promoted a tougher version of the bill with a formula that would track state violations over a 25-year period. It would immediately place a dozen or so states under federal oversight, including North Carolina, South Carolina, Texas, Florida and New York.

But as of right now, neither bill is going anywhere anytime soon. Representative Bob Goodlatte of Virginia, the chairman of the House committee that would most likely move the bill, the Judiciary Committee, has indicated he has no interest in giving the topic a hearing. Speaking with reporters at a Christian Science Monitor breakfast in Washington earlier this year, Goodlatte argued that no changes were called for because “there are still very, very strong protections in the Voting Rights Act.”

With that in mind, I asked Lewis how likely it was that either of his bills would move onto the floor in the near future. “I think that we may not be able to get something signed into law by the election,” he conceded. That said, Lewis argued, if one of them were to come up for a vote, it would be hard for some Republicans to be on record voting against it — a point that Democrats and Republicans alike agreed with when I spoke with them this week. But even if a bill were to pass through Congress, it would still most likely wind up before a Supreme Court that is already on record as being exceedingly hostile to any such law.